for vet. students

2. Fluid Therapy
Submitted to Dr. Khurram Ishfaq
Submitted by Group 3

3. Body Fluid
• Basics of body fluids and its
composition.
• Water balance in body.
• Regulation of body fluids.
• Fluid therapy &its indication.
• Types of fluids.
• Routes of administration.
• Fluid over load signs.

4. Basics of Body Fluid:
• An adult animal contains about 60% fluid of its body weight.
• Intracellular fluid (ICF) consists of about two-thirds of total body
fluids.
• The extracellular fluid (ECF) which constitutes about one-third of the
total body fluids. It is divided into three sub compartments—
interstitial, intravascular, and trans cellular. The interstitial contains
three-quarters of all the fluid in the extracellular space.
• The intravascular contains the fluid, mostly plasma, that is within the
blood vessels. Total blood volume is roughly 8% of bodyweight and
plasma roughly 5% of bodyweight

5. Continue............
• The fluid in the trans cellular compartment is produced by specialized
cells responsible for cerebrospinal fluid, gastrointestinal fluid, bile,
glandular secretions, respiratory sections, and synovial fluids.
• Daily water intake is about 10% of the body weight (can vary from
animal to animal with respect of their age, environment, feed intake
etc. ).
• Daily water loss equals daily intake and this loss occurs through the
skin, lung, kidney and gastrointestinal tract.

6. Continue............
• Body water contains solutes (substances that dissolve in
solvent; particles).
• Electrolytes are substances that split into ions when placed
in water.
• Primary ions in the body are sodium, potassium, chloride,
phosphate, and bicarbonate.
• Cations are positively charged ions.
• Anions are negatively charged ions.
• Body water is the solvent in biological systems
• To establish equilibrium, body water moves along its
concentration gradient

7. Composition of fluid.
• ICF Ca,Mg,K,PO4,protien.
• ECF Na,Cl,HCO3.
Ca 2+
Mg 2+
K+
Na+
Cl-
PO4
3-
Organic
anion
HCO3
-
Protein
0
50
50
100
150
100
150
Cations Anions
ECFICF

8. Fluid therapy Types:
• Replacement therapy:
Therapy in which we infuse same type of fluid
which is lost from body .
• Adjunctive Therapy:
One type of fluid is given to remove other type of
fluid e.g. mannitol 25% is given in case of ascites and edema.
• Supportive Therapy:
Fluid is given to animal just to support him to cure
quickly i.e. amino acids, minerals, multivitamins and carbohydrates etc.

9. Indications:
• Fluids are administered to patients not only to replace fluid loss but
also to correct electrolyte abnormalities, promote kidney diuresis,
and maintain the tissue or organ perfusion.
• During shock.
• Dehydration.
• Diuresis (Toxicities , renal diseases).
• After surgical procedure i.e. to prevent hypotension as hypotension
may be due to vasodilation, decreased cardiovascular function etc.
• Acid base abnormalities.
• Electrolyte abnormalities.

10. Dehydration:
• Dehydration or the loss of fluid
from the interstitial space in the
form of increased fluid loss from
vomiting, diarrhea, or polyuria is
one of the main cause of water
reduction in body.
• Signs include decreased skin
tenting, sunken eyes, depressed
mentation, and tacky/dry
mucous membranes, CRT 2-3 sec
in mild cases and >3 sec in severe
cases, Slight depression of eyes
into sockets.

11. Diagnosing Dehydration:
• Physical exam
• Weight loss
• PCV (HCT) increased
• Albumin or total protein increased
• BUN, creatinine
• Prerenal azotemia

12. Clinical examination of Degree of
Dehydration
Degree of Dehydration(%) Clinical signs
<5 Not clinically detectable.
5-6 Subtle-loss of skin elasticity
6-8 Obvious delay in return of tented skin.
Slightly ↑ CRT
Eye possible sunken & dry mucous membrane.
10-12 Skin remain tented.
Very prolonged CRT.
Sunken eyes & dry mucous membranes.
Possibly signs of shock (tachycardia, cool extremities,
rapid & weak pulse)
12-15 Obvious signs of shock.
Death imminent

13. Shock :

14. Types of fluid:
(a) Crystalloids.
• Contain sodium as the main osmotically active
particle.
• Useful for volume expansion (mainly interstitial
space).
• For maintenance infusion.
• Correction of electrolyte abnormality.
• Types of crystalloids
• Isotonic crystalloids
Lactated Ringer’s, 0.9%NaCl(Normosol)
• Only 25% remain intravascularly

15. Continue.........
• Hypertonic saline solutions
3% NaCl
0.9% normal saline with 5% dextrose
10% dextrose in water
• Hypotonic solutions
D5W(dextrose 5 % in water)
0.45% NaCl
0.25% NaCl
less than 10% remain intravascularly, inadequate
for fluid resuscitation.

16. Lactated Ringer’s Solution:
• Composition closely resembles ECF
• Contains physiological concentrations of: sodium, chloride,
potassium, and calcium
• Also contains lactate, which is metabolized by the liver alkaline-
forming
• Because small animals that are sick or under anesthesia tend towards
acidosis

17. Ringer’s Solution:
• Same as LRS except no lactate added
• Commonly used in Large animals
• Large animals who are sick tend towards alkalosis instead of acidosis

18. Normal Saline:
• 0.9% Sodium chloride = ISOTONIC
• Lacking in K+, Ca2+
• Used for hyperkalemia, hypercalcemia
• Used as a carrier for some drugs
• Used if don’t want lactate

19. (b) Colloids
• Contain high molecular weight
substancesdo not readily migrate across
capillary walls
• Preparations
- Albumin: 5%, 25%
- Dextran
- Gelifundol
- Haes-steril 10%

20. Natural Colloids
• Blood products:
• Whole blood
• Plasma
• Platelet-rich plasma
• Packed RBC’s

21. Synthetic Colloids
• Dextrans, Hetastarch
• Used when quantity of a crystalloid is too great to be able to infuse
quickly
• Stays within the vasculature maintain blood pressure
• Duration of effect is determined by molecular size:
• bigger = longer
• Small volumes produce immediate increases in blood pressure

22. Routes of Fluid administration
Route of administration Advantages Disadvantages
Oral •Safest route
•Easy
•Less rapid absorption
•Possible aspiration
•Cannot use for vomiting animals
Subcutaneous •Relatively easy to administer
•Absorption distributed over time
•Possible infection
•Must use isotonic fluids
•Slower absorption

23. Route of
administration
Advantages Disadvantages
Intravenous •Precise amount given is
available rapidly
•Various tonicities of
fluid can be used
•Possible fluid overload
and vessel damage
•Requires close
monitoring
•Must be sterile
Intraperitoneal •Relatively rapid
absorption
•Can be used when IV
access is not available
•Possible infection
•Cannot use hypertonic
solutions
•Abdominal surgery
hindered after
administration
Intraosseous •Useful for small
animals, birds, and
pocket pets
•Can be used when vein
inaccessible
•Rapid absorption
•Lack of confidence in
administering fluid via this
route
•Possible infection
Rectally •Good absorption •Not frequently used

24. Fluids: How Much to Give?
• Correct dehydration
• Weight in kg times percent dehydration equals the amount
in liters that the animal is dehydrated
• Example: 10 kg animal who is 8% dehydrated
• 10kg X 0.08 = 0.8 liters
• Patient is lacking 0.8 liters, or 800 ml fluids

25. So How Is It Delivered?
• Infusion pump (easy)
• IV drip set: drops per ml written on package
• Regular Drip sets have 10, 15, or 20 drops per ml
• Med – large dogs
• Micro drip sets have 60 drops per ml
• Small dogs - cats

26. Calculate Drops Per Hour
• Calculate ml/hr.
• Calculate drops/hr by: ml/hr X drops/ml (from the package)
• Gives you drops needed in an hour
• Example: 100 ml X 10 drops per ml = 1000 drops in the first hour

27. Calculate Drops Per Minute
• Divide drops per hour by 60 min/hr to get drops per minute
• Ex: 1000 drops/ hr divided by 60 minutes per hour = 16.7 drops per
minute
• 16.7 drops/min divided by 60 sec per min = 0.28 drops/sec

28. Principles of Rehydration:
• Correct dehydration, electrolyte, and acid-base abnormalities prior to
surgery
• . Do not attempt to replace chronic fluid losses all at once
• Severe dilution of plasma proteins, blood cells and electrolytes may
result
• Aim for 80% rehydration within 24 hours
• Monitor pulmonary, renal and cardiac function closely

30. For example.
• An adult 18kg cat with 6% dehydration comes into the clinic. It is
estimated that the cat vomited 150 ml of fluid overnight
• Maintenance fluids can be dosed at 50 ml/kg/day in adults and 110
ml/kg/day in young animals
• Calculate maintenance volume
18kg x 50 ml/kg/day = 900ml per day
• Rehydration fluid is based on the estimated percent of dehydration
% dehydration x weight in kg = deficit in liters

31. Continue........
• Calculate replacement for dehydration
6% = 0.06
0.06 x 18 kg = 1.08 l
1.08 l x 1,000 ml/l = 1080 ml
1080ml x 0.8 (80% of dehydration value
replaced in 24 hours) =840 ml to replace
on first day
• Take estimated volume lost in fluid and add to the other volumes
• Final step: Take all values and add together
900ml + 840 ml + 150 ml = 1890ml

32. Fluid overload:
• Serous nasal discharge
• Increased respiratory rate (Dyspnea)
• Crackles or muffled lung sounds on pulmonary auscultation
• Late stage consequence = pulmonary edema (or pleural effusion in
cats)
• Decreased PCV
• Increased BP